104,582 research outputs found
Elasticity of demand for gasoline in the South Coast Air Basin
An analysis of California gasoline sales was made, using Box and Jenkins' linear time series methods, in an attempt to detect the change due to a 17% change in price. There was no detectable change within the 2% noise limit of the method. Thus, either the elasticity is less than 2 parts in 17, and/or the tools must be further refined to detect it
Growth of Sr1-xCaxRuO3 thin films by metalorganic aerosol deposition
We report the growth of thin films of Sr1-xCaxRuO3 on SrTiO3 and MgO
substrates by metalorganic aerosol deposition. The structure and microstructure
is characterized by X-ray diffraction and room-temperature scanning tunnelling
microscopy (STM), respectively. STM indicates in-plane epitaxy and a small
surface roughness for films on SrTiO3. The high-quality of the films is
supported by large residual resistivity ratios up to 29.Comment: 4 Pages, 2 Figures, submitted to Proceedings of ICM 2009 (Karlsruhe
Snakes and ladders: localized solutions of plane Couette flow
We demonstrate the existence of a large number of exact solutions of plane
Couette flow, which share the topology of known periodic solutions but are
localized in space. Solutions of different size are organized in a
snakes-and-ladders structure strikingly similar to that observed for simpler
pattern-forming PDE systems. These new solutions are a step towards extending
the dynamical systems view of transitional turbulence to spatially extended
flows.Comment: submitted to Physics Review Letter
Implications of the isotope effects on the magnetization, magnetic torque and susceptibility
We analyze the magnetization, magnetic torque and susceptibility data of
La2-xSrxCu(16,18)O4 and YBa2(63,65)CuO7-x near Tc in terms of the universal
3D-XY scaling relations. It is shown that the isotope effect on Tc mirrors that
on the anisotropy. Invoking the generic behavior of the anisotropy the doping
dependence of the isotope effects on the critical properties, including Tc,
correlation lengths and magnetic penetration depths are traced back to a change
of the mobile carrier concentration.Comment: 5 pages, 3 figure
Brain homeostasis : VEGF receptor 1 and 2 ; two unequal brothers in mind
Vascular endothelial growth factors (VEGFs), initially thought to act specifically on the vascular system, exert trophic effects on neural cells during development and adulthood. Therefore, the VEGF system serves as a promising therapeutic target for brain pathologies, but its simultaneous action on vascular cells paves the way for harmful side effects. To circumvent these deleterious effects, many studies have aimed to clarify whether VEGFs directly affect neural cells or if the effects are mediated secondarily via other cell types, like vascular cells. A great number of reports have shown the expression and function of VEGF receptors (VEGFRs), mainly VEGFR-1 and -2, in neural cells, where VEGFR-2 has been described as the major mediator of VEGF-A signals. This review aims to summarize and compare the divergent roles of VEGFR-1 and -2 during CNS development and homeostasis
Magnetic Field Induced Phase Transitions in YBa2Cu4O8
The -axis resistivity measurements in YBa_2Cu_4O_8 from Hussey et al. for
magnetic field orientations along the c-axis as well as within the ab-plane are
analyzed and interpreted using the scaling theory for static and dynamic
classical critical phenomena. We identify a superconductor to normal conductor
transition for both field orientations as well as a normal conductor to
insulator transition at a critical field H_c||a with dynamical critical
exponent z=1, leading to a multicritical point where superconducting, normal
conducting and insulating phases coexist
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